Depressed pressure cap



Jan. 1, 1963 D. FRIEND DEPRESSED PRESSURE CAP Filed Oct. 7, 1959INVENTOR. DAWSON FRIEND ATTORNE Y United States Patent 3,071,285DEPRESSED PRESSURE CAP Dawson Friend, Connersville, 11111., assignor toStant Manufacturing Company, Inc., Connersville, Ind., a corporation ofIndiana Filed Oct. 7, 1959, Ser. No. 844,893 7 Claims. (Cl. 220-44) Thepresent invention relates to closure means for the filling openings oftanks, and has been designed primarily for use in automobile enginecooling systems of the open type in which the system operates normallyunder substantially atmospheric pressure. While the invention has beenillustrated and will be described in connection with such coolingsystems, it will be appreciated that it may be useful, as well, in otherenvironments.

In such open type cooling systems, it is conventional to provide afiller neck which is a tubular element secured to the top wall of theradiator tank in registry with the filling opening in that wall andextending upwardly therefrom to provide a lip retainingly engageable bythe cover element of a closure cap. The filler neck further provides, ata level below such lip, a seat adapted for closing engagement by anannular valve reciprocably supported from the cover element andresiliently urged into such engagement when the cover element is inplace on the lip. A normally open valve is associated with the port inthe annular valve means in such fashion as to close that port inresponse to a sudden and substantial increase in pressure within thetank; but under normal conditions, the interior of the tank is in opencommunication with an overflow pipe.

It has been found that, in such systems, the conventionalcoolant-circulating pump returns the liquid coolant to the tank soforcefully, at times, as to produce such a. degree of surging in thetank as causes the coolant to be splashed out through the open valveport, to be lost through the overflow pipe; and that such splashing,which may also be produced in part by the motion of the vehicle, mayultimately result in the loss of such a quantity of coolant liquid as tocause overheating of the engine with which the cooling system isassociated.

The primary object of the present invention, therefore, is to providemeans which will guard against the loss of coolant without interferingwith the normal operation of the valving mechanism carried by theclosurecap in such a system.

Further objects of the invention will appear as the descriptionproceeds.

To the accomplishment of the above and related objects, my invention maybe embodied in the forms illustrated in the accompanying drawings,attention being called to the fact, however, that the drawings areillustrative only, and that change may be made in the specificconstructions illustrated and described, so long as the scope of theappended claims is not violated.

FIG. 1 is a somewhat diagrammatic, fragmental view of the upper portionof one form of conventional automobile radiator, parts being broken awayfor clarity of illustration;

FIG. 2 is a fragmental section of a part of the radiator of FIG. 1,showing my novel closure means, and drawn to an enlarged scale;

FIG. 3 is a view similar to FIG. 1 but showing a different form ofradiator; and

FIG. 4 is a section similar to FIG. 2 but showing the closure meansinstalled in a radiator of the character illustrated in FIG. 3.

Referring more particularly to the form of invention illustrated inFIGS. 1 and 2, it will be seen that I have indicated an automobileradiator including a tank portion 14) having a top wall 11 formed with afiller opening 12 (FIG. 2) in a depressed portion 13 of said wall, afiller neck assembly, indicated generally by the reference numeral 14,being associated with the opening 12. The depression 13 and thearrangement of the opening 12 in that depression provides for theestablishment of an air space 15 at the top of the tank. This is, ofcourse, desirable to provide for expansion of the liquid body in thetank without overflow thereof.

Referring more particularly to FIG. 2, the assembly 14 comprises afiller neck having a tubular body 16 provided, at its upper end, with anoutturned lip 16 defining an annular seat 17 and terminating in adownturned flange 18 formed with cam surfaces 19 at its lower edge, inaccordance with conventional practice. Intermediate its ends, the body16 is shaped to provide an inturned portion 2% adapted to be welded orotherwise suitably secured to the portion 13 of the top wall 11; and theinner peripheral region of the flange 20 is formed to define an annularseat 21 for a purpose which will become apparent.

Between the levels of the seats 17 and 21, the body 16 is formed with alateral overflow port 22 with which communicates an overflow conduit 23.All of the structure thus far described is conventional.

According to the present invention, the body 16 is further provided witha downward, tubular extension 24 which penetrates the opening 12 andextends into the tank 10 to a level significantly below the wall portion13 where it terminates in an open mouth 25. At a level substantiallyabove the level of the mouth 25, and preferably closely adjacent thewall portion 13, the extension 24 is formed with a small-diameter bleedport 26 in which is supported, in this form of the invention, one end ofa I bleed tube 27 the other end 28 of which is upwardly direeted andpreferably disposed adjacent the level of the major portion of the topwall 11. At any rate, the open end 28 of the tube 27 is disposed withinthe air chamber 15. The optimum level for the liquid coolant within, the

, tank is indicated at 29 and is at'the level of the mouth 25 of thefiller neck extension 24-.

While the extension 24 is preferably an integral part of the body 16, ashere illustrated, it will be clear that it may,

' alternatively, be a separate element suitably fixed in the wallopening 12.

The closure cap of the present invention is indicated generally by thereference numeral 30 and comprisesa cover member 31 provided with askirt portion terminating in inturned fingers 32 for cooperation withthe cammed surfaces 19 of the flange 18 of the filler neck 16, inaccordance with conventional practice. The cover member 31 is centrallyperforated to support fixedly a I bell-shaped element 33 whose loweredge is outturned to define a broken peripheral lip 34. A secondbell-shaped element 35 has an inturned flange 36 which is reciprocablysupported upon the element 33. The lower end of the element 35 is formedto define an annular pan 37 upon whose lower face is supported anannular gasket 38. A coiled spring 39 is confined between a shoulder 40on the element 35 and a flexible diaphragm 41 which, when the cap is inplace on the filler neck, bears upon the seat 17. The spring 39resiliently holds the element 35 in its lowermost position with respectto the element 33 and therefore, when the cap is in place, resilientlypresses the gasket 38 against the seat 21.

The element 35 is formed to provide an inturned annular seat 42 facing apartition 43 which is fixed within the element 35. As shown, thepartition 43 is formed with a central port 44 and a plurality ofeccentric ports 45 and, on its upper face, provides a plurality of smallprotrusions 46. A valve member 47 is freely mounted within the element35 and is confined between the partition 43 and the seat 42. Said valve47 normally rests upon the protrusions 46 and there is a substantialclearance between the external periphery of the valve 47 and theinternal periphery of the element 35.

Fixedly mounted with respect to the partition 43 is an invertedbell-shaped member 48, the lower end of which carries a flexible gasket49 which is centrally secured to the element 48 by any suitable meanssuch as the rivet assembly 50. The external diameter of the gasket 49 isat least equal to, and preferably somewhat larger than, the internaldiameter of the extension 24; and the parts are so proportioned andarranged that, when the cover member 31 has its fingers 32 retaininglyengaged with the cammed surfaces 19 of the filler neck flange 18, thegasket 49 will be positioned within the extension 214 at a level betweenthe mouth 25 and the bleed port 26. In the optimum form of theinvention, the gasket 49, when so located, will be downwardly convex, asshown.

With the parts in their illustrated positions, it will be clear thatgradual variations in the pressure within the tank will be equalized bygas or vapor flow through the tube 27 and bleed port 26, since gas orvapor can flow freely through the ports 51 in the elements 48, 44 and 45in the partition 43 and 52 in the element 33 to the overflow pipe 23.The gasket 49, however, seals the lower end of the extension 24 againstthe passage of surging liquid from the tank 10. While said gasket issufliciently flexible so that any substantial excess of pressure withinthe tank over atmospheric pressure will flex the perimetral region ofthe gasket upwardly to permit fluid flow therepast, mere splashing andsurging of the liquid will not create a suflicient force to flex thegasket out of sealing engagement with the inner peripheral wall of theextension 24.

Obviously, any sudden increase in pressure within the tank 1%) will thusflex the gasket 49 and force the valve 47 into sealing engagement withthe seat 42; and if the accumulated pressure attains suflicient value,the gasket 38 will be forced off its seat 21 to permit fluid flow pastsaid gasket to the overflow pipe 23.

In the form of invention illustrated in FIGS. 3 and 4,

the tank 60 is formed with a planar top wall 61 which is provided with afiller opening 62 with which the filler neck assembly 14 is similarlyassociated. The extension 24 is in all respects similar to the extension24 and is provided with a bleed port 26. In this case, no equivalent ofthe tube 27 is used.

The closure cap assembly 30 is identical with the assembly 30 of FIG. 2and cooperates in a similar fashion with the filler neck 14, the gasket38 being resiliently held against the seat 71 and the gasket 49 beingsimilarly positioned in the extension 24' between the lower open mouthof that extension and the bleed port 26.

The extension 24' provides for maintenance of an air space 65 in thetank 60. That is, it is the usual practice of attendants in servicestations to pour water into the filler neck of a radiator until wateroverflows the upwardly opening mouth of the filler neck. With thearrangement herein disclosed, when the liquid in the tank 10 or 60reaches the level 29 or 79, further liquid poured into the filler neckwill quickly rise therein and overflow the upper end of the filler neck.The relatively small 4 amount of liquid remaining in the filler neckwill drain through the lower open mouth of the extension 24 or 24'without substantially raising the level 29 or 79; and pressures will beequalized through the pipe 27 or port 26'.

When the cap 30 is associated with the tiller neck 14, the diaphragm 41will engage the seat 67 and the gasket 38 will be resiliently pressedagainst the seat 71, while the gasket 49 will be positioned within theextension 24 at a level between the lower open mouth of said extensionand the bleed port 26'. The operation of the arrangement illustrated inFIGS. 3 and 4 is identical with that of the arrangement illustrated inFIGS. 1 and 2.

I claim as my invention:

1. In a system of the class described, a tank having a top wall, afiller neck mounted in and penetrating said top wall, said filler neckbeing formed to provide an upper mouth, an annular upwardly-facing seatbelow said mouth, and a tubular extension below said seat andterminating in a lower mouth disposed Within said tank at a levelsignificantly below said tank top wall, said neck being provided with anoverflow port between said upper mouth and said seat, and said extensionbeing provided with a bleed port between said lower mouth and said tanktop wall, and a closure cap for said filler neck, said cap including acover member rctainingly engageable with said neck to span and coversaid upper mouth, ported valve means reciprocably supported from saidcover member and yieldingly pressed into closing engagement with saidseat when said cover member is so engaged, a second valve meansconstructed and arranged to close the port in said ported valve means attimes but biased to open position, and a gasket centrally supported fromsaid cover member and disposed, when said cover member is so engaged,within said extension at a level between said lower mouth and said bleedport and in peripheral engagement with said tubular extension.

2. In a system of the class described, a tank having a top wall formedwith a port therein, a tube registering with said port, extending intosaid tank and terminating therein in a downwardly-opening mouth disposedat a level significantly below said wall, said tube body being providedwith a bleed port between said wall and said mouth, a filler necksecured to said wall in registry with said port and providing anupwardly-opening mouth outside said tank and an upwardly-facing seat,said neck further being provided with an overflow port between said seatand said upwardly-opening mouth, and a closure cap including a covermember retainingly engageable with said neck to span and cover saidupwardly-opening mouth, ported valve means reciprocably supported fromsaid cap and yieldingly urged, when said cover member is so engaged,against said seat, a second valve means constructed and arranged toclose the port in said ported valve means at times, but biased to openposition, and a gasket centrally fixedly supported from said portedvalve means and disposed, when said ported valve means is on said seat,within said tube at a level between said downwardly-opening mouth andsaid bleed port and in pheripheral sealing engagement with said tube.

3. The combination of claim 2 in which said gasket is axially flexible.

4. The combination of claim 3 in which said gasket is downwardly-convex.

5. The combination of claim 2 in which the port in said tank top wall isformed in a depressed region of said wall, and a conduit leads from saidbleed port and opens into the interior of said tank at a point spacedfrom said depressed region and at a level above the level of said seat.

6. In a radiator for an automobile engine cooling sys tem or the like,said radiator having a tank including a top wall formed with a filleropening, a tube registering with said opening and extending into saidtank to terminate in a downwardly-opening mouth disposed at a levelsignificantly below said wall, said tube being formed, within said tank,with a bleed port at a level beneath but closely adjacent said tank topwall, and a closure for said opening, said closure carrying acentrally-supported baffle disposed, when said closure is in operativeposition, Within said tube at a level between said mouth and said bleedport.

7. The combination of claim 6 in which said bafiie is anaxially-flexible gasket proportioned and arranged, when so disposed, forsealing peripheral engagement with the 1() internal wall of said tube.

References Qited in the file of this patent UNITED STATES PATENTS SmithJuly 4, 1939 Le'bus Nov. 23, 1954 Pipes et al Dec. 22, 1959 FOREIGNPATENTS Great Britain June 27, 1929 Great Britain I an 5, 1942

1. IN A SYSTEM OF THE CLASS DESCRIBED, A TANK HAVING A TOP WALL, AFILLER NECK MOUNTED IN AND PENETRATING SAID TOP WALL, SAID FILLER NECKBEING FORMED TO PROVIDE AN UPPER MOUTH, AN ANNULAR UPWARDLY-FACING SEATBELOW SAID MOUTH, AND A TUBULAR EXTENSION BELOW SAID SEAT ANDTERMINATING IN A LOWER MOUTH DISPOSED WITHIN SAID TANK AT A LEVELSIGNIFICANTLY BELOW SAID TANK TOP WALL, SAID NECK BEING PROVIDED WITH ANOVERFLOW PORT BETWEEN SAID UPPER MOUTH AND SAID SEAT, AND SAID EXTENSIONBEING PROVIDED WITH A BLEED PORT BETWEEN SAID LOWER MOUTH AND SAID TANKTOP WALL, AND A CLOSURE CAP FOR SAID FILLER NECK, SAID CAP INCLUDING ACOVER MEMBER RETAININGLY ENGAGABLE WITH SAID NECK TO SPAN AND COVER SAIDUPPER MOUTH, PORTED VALVE MEANS RECIPROCABLY SUPPORTED FROM SAID COVERMEMBER AND YIELDINGLY PRESSED INTO CLOSING ENGAGEMENT WITH SAID SEATWHEN SAID COVER MEMBER IS SO ENGAGED, A SECOND VALVE MEANS CONSTRUCTEDAND ARRANGED TO CLOSE THE PORT IN SAID PORTED VALVE MEANS AT TIMES BUTBIASED TO OPEN POSITION, AND A GASKET CENTRALLY SUPPORTED FROM SAIDCOVER MEMBER AND DISPOSED, WHEN SAID COVER MEMBER IS SO ENGAGED, WITHINSAID EXTENSION AT A LEVEL BETWEEN SAID LOWER MOUTH AND SAID BLEED PORTAND IN PERIPHERAL ENGAGEMENT WITH SAID TUBULAR EXTENSION.